Heating apparatus and control means therefor



E. J. DILLM'AN 2,139,615

HEATING APPARATUS AND CONTROL MEANS THEREFOR 5 Sheets-Sheet 1 Dec. 6, 1938.

Original Filed May 19, 1934 Dec. 6, 1938. E. J. DILLMAN TUS AND CONTROL MEANS THEREFOR Original Filed May 19, 1934.

HEATING APPAHA 3 Sheets-Sheet 2,

INVENTOR Dec. 6, 1938. E. J. DILLMAN HEATING APPARATUS AND CONTROL MEANS THEREFOR Original Filed May 19, 1954 3 Sheets-Sheet 3 INVENTOR 6W7 a ATTO EY Patented Dec. 6, 1938 UNITED STATES ammo APPARATUS AND com'iwr.

- MEANS 'rnaaaron Eamest J. Dillman, Detroit, Mich assignor to Detroit Lubricator Company, Detroit, Mich, a corporation of Michigan Original application May 19,"1934,' Serial No. v 726,586. Divided and this application Scptem-r her 7, 1935, Serial No. 39,578

] -2o (or 200-1301],

,, This application is a division .of my copending application, Serial No. 726,586, filed May 19,; 1934. My invention relates generally to new and useful improvements in control means such as an automatically operated 1 electric switch means which is particularly adapted for controlling the operation of a heating apparatus.

An object of my invention is to provide an elec the switch having safety means to permit overtravel of the switch operating means.

Another object is to provide a plurality of electric switches having a common operating means.

Another object is to provide means by which the range of operation of the electric switch by the automatic means may be readily regulated:

The invention consists in the novel control of the heating apparatus and in the improved construction and.combination of parts of the control means,- to be more fully described hereinafter and the novelty :of, which will be particularly pointed-out and distinctly claimed;

In the accompanying drawingspto be taken as a part of thisspeciflcation, I have. fully and clearly illustrated a preferredembodiment of my invention,-in which drawings-e Figure 1 is a diagrammatic viewof a heating apparatus embodying my control means;

Fig. 2 is a view in front elevation of the control means with the cover member of the casing removed;

Fig. 3 is a view in section substantially on the line 3-3 of Fig. 2;

Fig. 4 is a view in section on the line 4-4 of Fig. 2;

Fig. 5 is a detail view of certain relay mechanism taken on the line 5-5 of Fig. 2;

Figs. 6 and 7 are detail views taken on the line 6-6 and 'I-l respectively of Fig. 3, and

Fig. 8 is an enlarged detail view in section on the line 3-3 of Fig. 2.

Referring to the drawings by characters of reference, I designates generally a supporting structure comprising a metal casing having a curved cylindrical side wall 2 closed by a rear wall 3 and having a front cover or closure memher 4. Projecting centrally from the rear wall 3 there is an elongated external supporting member 5 having a longitudinally extending bore 6 therethrough in which an operating shaft 7 is rotatably supported. The shaft I is provided with a thermostatic actuating means 8 such as a helical coil of bimetal which surrounds the end of the shaft 1 which projects from the member 5. The coil 8 has one end secured, as at 9, to the member 5 and has its other end secured, as at It, to the end of the shaft 1. A tubular perforated shield II is preferably provided for the coil 8 and is fitted on the rear end portion of the member 5. A supporting plate l2 surrounds the member 5 and serves as a means for securing the control meansin' operative position in a furnace bonnet, for example. The end l3 of the shaft 1 which projects into the casing extends through a bearing sleeve, l4 which is screw-threaded or otherwise secured, as at 15, in the bore of the member 5. Fixed on the shaft end l3 there is a crank member iiwhich is held against rotation relative to the shaft by a clamping screw l1.

Projecting rearwardly from the free end of the crank member l6 thereis a rod or pin l8 which lies in parallel spaced relation to the shaft 1 and which terminates adjacent the rear wall 3. J ournaled about'the shaft 1 within the casing there is'a supportingplate or member i8 which is apertured to receive'the bearing sleeve It. The front face of the plate 18 abuts the rear face of a flange 20 rigid with therbearingsleeve and is held thereagainst by a'heiical coil-spring 2|. The spring 2| .18 extends radially from the shaft 1 in substantially parallel relationto-the wall 3 and terminates adjacent theslde wall 2 where it is provided with a forwardly extending flange 22.

Through-thewall '2 there is a circumferentially extending slot 23 which overlies the flange 22 and which is closed by a slidable elongated closure strip 24 interposedbetween the wall 2 and the flange 22. The supporting plate i8 is adjustable about the shaft 1 and is held in adjusted position by a clamping screw 25 which travels in the slot 23 and carries the strip 24 and which is screwthreaded through the flange 22. interposed between the head 28 of the screw 25 and the outside face of the wall 2 there is a clamping plate 21 which is held against rotation by depending fingers projecting into slot 23 and which is clamped into frictional engagement with the outside face of the wall 2 by the head 26 to hold plate l9 against movement. The plate 21 has a pointer or finger ,21 cooperable with suitable indicia. extending circumferentially of the wall 2. On the front face of the plate 18 there is a metal supporting block 28 which extends longitudinally thereof and is fixed in position by screws 29. The block 28 is insulated from the plate i9 by electric insulating pads 38. Extending transversely through the outer end portion of block 28 and parallel to the plane of plate I9 there is a contact member I! which is adjustably screwthreaded through the block and which is held in adjusted position by a clamping screw 32. Also supported in the block 28 there is a permanent bar magnet 33 which is fixed in a sleeve 34 adjustably screw-threaded through the block 28. The magnet 23 is positioned intermediate the contact member 3| and the shaft 1 and parallel and adjacent to the contact member 3|. On the inner end of the block 28 there is a binding post or screw Surrounding the sleeve |4 there is a disk or abutment member 35 of electric insulating material which bears against the front face of flange 25. Spaced from the disk 35 there is a disk or abutment member 31 also of electric.

insulating material which surrounds 'thesleeve i4. Interposed between and abutting disks 35,31 there is a tubular insulating and spacermember 38 which surrounds the sleeve |4. Journaled about the shaft 1 between the disks 35, 81 there is a switch arm designated generally by the numeral 35 which comprises a metal disk 48 .aper-rtured to receive the tubular -member 38 and bearing against the rear face of the abutment member 31. Extending radially from the periphery of the disk 45 there is a flange 4| having a rearwardly extending portion 42 parallel to shaft contact members 45 and 3| are in engagement with each other. Projecting radially from the periphery of the disk 40 there is an abutment member, which lies-substantially opposite the flange 4| and which also serves as a binding post having a binding screw 41. Surrounding'the tubular member 38 there-is a .tubular metal spacer member 41! which substantially flts between the disk-35 and the switch arm disk 48 to hold the 35. against disk 31 without preventing free rotation -.of disk 40.. :A spring .48, under tension. surrounds a spacer. member 41!, and has one end anchored, as

disk 45 againstaxial movement and substantially at-45, =to the'rod l8 andhas its other end anchored, as still, rto the abutment 45 so-that the spring normally tends to urge the abutment 45 and the rod |8 into engagement with each other. It will benoted that the-spring 48' serves as a lost-pmotioniconnection between the crank member 5 and the switch arm 39 so that when the contactmember 45 is moved by operation of shaft 1 into engagement with contact member 3|, the rod 8 may move away from abutment member 45 against the tension-of spring 48. The free end of sleeve I4 is provided with a lateral flange 5| carried by a screw which is threaded into the bore of the sleeve and which is longitudinally apertured for passage of the shaft end |3 therethrcugh. Abutting the rear face of the flange 5] there is an abutment disk 52 of electric insulating material which is apertured to receive the sleeve l4. Also surrounding the sleeve |4 there is an abutment disk 53 of electric insulating material which is spaced from the disk 52 by a tubular insulating member 54 surrounding sleeve l4. Bearing against the rear face of abutment disk 53 there are a pair of overlapping supporting plates or members 55, 55 which are in abutting relation, the plate 55 engaging the rear face of plate 55. Interposed between the abutment disk 31 and the plate 55 there is a helical coil spring 51 under compression and which holds the disk 31 against tubularmember 35 and the plates 55, 55 against the disk 53. The plates 55 and 55 extend radially from the shaft 1 with the plate 55 terminating adjacent the wall 2 in a forwardly extending curved flange 58. Parallel to the slot 23 there is a circumferential slot 55 through the wall 2 which overlies the flange 58, the slot being closed by a slidable closure strip 58 which is interposed between the wall 2 and the flange 55. The plate 551s adjustable about the shaft I and is provided with a clamping means 5| such as a screw passed through the strip 55 and threaded into the flange 58, the screw having a head 52 by which the plate 55 may be adjusted and clamped in position. Interposed between the head 52 and the side wall 2 there is a clamping plate 53 having'flngers depending into the slot 55 and having a pointer similar to the pointer on the plate 21 and cooperable with suitable indicia on the cir- .-cumference ofthe wall 2. The plate 55 terminates short of the wall 2 and is adjustably fixed to the plate 55 for movement therewith, the plate 55- being .cIamped to plate 55 by a screw 54 threaded into plate 55 and extending through a slot 55 in the plate 55. Extending longitudinally of the plate 55 there is a metal supporting block 55 which is adjacent the side edge of plate 55 opposite the plate iliw Adjustabl'y screw threaded transversely :thro'ugh-the block 55 adjacent and the shaft 1. On the inner end-of the-block 55 .there is :a binding screw 10. "The block 55 is secured to the-plate 55 by screws" and isinsulated fromthe plate 55by-pads of insulating ma.-

terialv 12. Extended longitudinally of thes'upporting plate 55 there isanelongated supporting block 13 which is-secured 'to the "plate "55 by screws .14 and electrically ='insulatedfrom the plate by pads of insulating material 15. *Adjust-' ably screw-threaded *transve'rsely through the outer end portion of 'the block -13"there is a contact member;15 which is positioned opposite the contact-member 51 and which lies substantially parallel to the supporting plate 55. Between the contact member 15 and the shaft 1 there-is a permanent bar magnet 11 fixed in an adjustable supporting sleeve'18 screw-threaded transversely through the block 13 andpositioned substantially opposite the magnet 58. On the inner end of the block 13 there isa binding screw 18. Journaled about the shaft end |3 there is a switch arm designated generally by the numeral 88 cooperable with and positioned between the contact members 51 and 15 and which comprises a substantially circular plate or disk 8| apertured to receive the tubular member 54. Surrounding the member 54 there is a tubular metal spacer member 8| which substantially fits between the disk 52 and the switch arm plate 8| to 'hold the plate 8| against axial'movement and substantially against the insulating disk 53 without preventing free rotation of plate 8|. A spring 82 surrounds the spacer member 8| and is under tension, having one end anchored to the crank member rod i8, as at 83, and having its other 'end anchored, as at 84, to an abutment member 85 which extends radially from the periphery of the plate 8| so that the spring tends to urge the abutment member 85 and the rod l8 into engagement with each other. The abutment member 85 also serves as a terminal post and is provided with a binding screw 85; On the periphery of disk 8| susbtantially opposite abutment 85 there is a flange 81 projecting radially from shaft 1 between blocks 55 and 13. The flange 81 has a forwardly extending portion 88 to which a rigid elongated backing strip or plate 88 is secured. Positioned on the opposite sides of the backing plate 88 there are resilient metal switch 80, 9I which are also secured to -the'flange portion 3 which is supported within the casing on. the'wall 2 to which it is secured by screws 85. The block 84 supports a relay switch mechanism having an electromagnet with-a coilwinding- 96 which is cooperable with an armature switch lever 81. On the end of .the lever 91 there is-a transversely extending contact blade 98 cooperable with spaced-contactmembers 99 to close a circuit between the members 99. The contact members 99 are supported by arms I00, IOI which'are rigidly secured to the block 84 by screws I02. The arms are provided respectively with binding po ts I03, I04, see Fig. 5. A spring I08 acts on the lever 91 and acts-to move and-hold the'contact arm 98 out of engagement with contacts "99 when the coil '98 is deenergized. Aconduit fitting I08 is provided in the wall 2 for the admission of lead wires into thecasingzfor binding posts.III8,-I04...

Secured to the outsiderface .of thewall 2 there is an insulating block I01 which carriesupper frontand rear binding posts I08; I09 and-lower 1 front and rear binding posts I I0, III. Thebinding post I08 is connected .to'the contactmember I8 by a lead wire I I2 which is secured to the block '13 by the binding screw 19. -The bindingpost I09 is connected-to the contact member 3| by. a lead wire II3 which is secured to the block" by the bindingscrew 35. Also connected to the block 28 by screw there is a lead wire I I 4 which is connected at its other end to the switch arm 80 by the binding screw 88. The contact member 81 is electrically connected to the binding. post. I by a lead wire II 5 which is secured to the block 89 by the binding screw 10. From the binding post IIO a lead wire II8 connects to one terminal of the magnet coil winding 98. From the other end or terminal of the coil 98 a lead wire H1 is conii icted to the switch arm 39 by the binding screw In Figure 1, I have shown the above described control means operatively connected in a heating system for controlling .the heating apparatus which includes a hot air furnace I I8 having draft inlet and check dampers II9, I20 respectively controlling combustion. The dampers are opera tively connected by pull chains I2I, I22 respectively to the lever arm I28 of an electrically operated damper actuating means I 24 which is preferably an electrically energized heat motor having an electrically heated bulb element I25 and an expansion chamber I25 for actuating the lever I23. The furnace II8 is provided with an air circulating fan I26 for increasing flow through the furnace bonnet I21 of air to be heated and supplied to a roonror other space. The fan I28 is driven by an electric motor I21 having lead wires I28, I29. The control means above described is positioned to respond to the temperature of the air in the furnace bonnet and has the rear end of member 5 and the thermostatic coil 8 inserted thereinto through a suitable aperture tively.-

connection to the with the plate I2 rigidly fixedto the bonnet wall and supporting the control means The lead wire I28 extends'through the fitting I08 and is secured to the terminal post I03of the relay switch mechanism.- From the other-terminal post I04 9. lead wire I80 extends'to a suitable source'of high volta'gecurrent supply; The lead wire I28 also connects to this-source of" current supply so thatt the motor I21 and the .relay switch mechanism are in series circuit. A transa former-HI has its primary side'connected by lead'wires "2,133450 the lead "Wire's I30, I28

'- respectively: so that the transformer is energized from the current source." Thetransformer secondary is connected by a lead wire I34 to'the upper front binding post I08 'andis connectedby a lead wire I88 to the lower front binding post 'I I0. From the binding post I08 a lead wire I36 extends to'a'room thermostat I31 positioned in a room or other space supplied with heated air from the furnace II8. From the other terminal of the switch mechanism of-the room thermostat I31 a lead wire I38 connects to the upper rear binding post I08. The electric heating means for the bulb element I25 of the damper actuating means is connected by lead wires I39, I40 to the front and rear binding posts IIO, I I I respec- The operation of my control means when em- :ployed for controlling the operation of the heating apparatus above described is as follows: In the 'drawings, referring in particular to'Figs.--1 and 2, "the parts are shownin-the'positionswhich they willassumewhenthe ro'om'thermostat I31 is sat- -isiled, that is, when -thetemperature of the'room has reachedthe desired degree for which the thermostat-is set and'when the'temperature or the air in the furnace bonnet is below the temperature at-which operation of the fan I28 is de sired. If the temperatureof the room should now decrease sothat the thermostat I31 calls for heat and-closes its'circuit between lead wires I38 and 138, then the following circuit will be established: from the transformer secondary through lead wire I84, terminal post I08, lead wire I36, thermostat I31, lead wire I38, terminal post I09, lead wire II3, binding'screw 38, lead wire II4 to switch arm 80 through engaged contacts 92, 81 to binding screw 10 and thence via lead wire II5 to terminal post III,from terminal post III through lead wire I40 to the heating element for bulb I25, the lead wire I39 to terminal post I I0 and thence through lead wire I35 back to the transformer secondary. The energization of the damper actuating means I24 will rotate the lever I23 clockwise, facing Fig. l, to increase the furnace draft by pulling upward on chain I2I to open the draft inlet damper H9 and by releasing chain I22 to permit damper I20 to close. As the temperature in the bonnet I21 increases due to opening of the draft and closing of the check dampers, the thermostatic coil 8 will rotate shaft 1 in a clockwise direction, facing Fig. 2, which will carry the switch arm 39 with it and move the contact mem ber toward its fixed contact member 3 I. When the temperature in the bonnet reaches the de-* sired minimum temperature at which fan-I26 may be eillciently operated to force air to be heated through the furnace bonnet, then the switch arm contact member 45 will be moved into engagement with contact member 8|. A circuit will now be completed from 'binding'screw 85 supplied with current from lead wire II8 as above described to switch arm 89 through the engaged contact members 3I and 45 and thence via lead wire I I1 to the relay coil 96 and from the relay coil throl'mh lead wire 'II6 to binding post IN and back to the transformer secondary via-lead wire I35. Energizatlon of the coil 96zwill attract lever arm 91 to engage lever arm- 99 with contact members 99 thereby closing the circuit to the fan motor I21 between lead wires I39 and I29. If the room temperature increases toa degree which satisfies theroom thermostatlfl, the thermostat I31 will breakits circuit between lead wires, I36 and I38 which will .cut off current flow to the lead wire coil 96 andthe damper actuating means I24 so tween the contact-members 92 and 61 will how- 3 thereby deenergizing the relay mechanism tinue to rotate due to the lost motion spring 48 and rod I8 and will move out of engagement with its abutment member 46 without, injury to the switch mechanism. Substantially at the maximum desired bonnet temperature the crank member rod I9 will engage the abutment 95 on switch arm 80 and will start to move .the arm 80 away from the supporting-block 66. Engagement beever not be broken until the exact-maximum temperature is reached asthe magnet 68 will exert its attractive force on resilient switch blade 90 until the blade 99 is tensioned by rotation of arm 90 sufllciently to overcome the-holding force of the magnet when contact between contact members 92 and 61 will be broken with a snap action. Disengagement of contact members 92 and 6|--will break circuit between lead wires I39, I 40 to deenergize the damper actuating means I24 to close the draft damper H9 and open check damper I as above described. The deenergization of the actuating means I24 will not however aflect operation of the .fan I26 which will continue in operation due to the engagement of switch arm 39 and contact member 3|. The fan I26 will continue in operation until the room thermostat I31 is satisfied. Should the room thermostat I31 become satisfied after maximum bonnet temperature is reached thereby stopping fan I26, the temperature of the bonnet might continue to increase, particularly with a coal-fired furnace, even though the draft damper is closed and the check damper open. If the bonnet temperature does continue to increase so that clockwise rotation of shaft I continues under the force of thermostatic coil 8, the switch arm 89 will move its contact member 93 into engagement with contact member I6. This will again start operation of the fan I26 to cool the furnace bonnet I21 and prevent injury to the furnace due to overheating. The fan circuit through the room thermostat having been broken, the safety fan circuit will be as follows: from the transformer secondary through lead wire I34, terminal post I08, lead wires 2, binding screw I9, closed contact members I6, 93, switch arm 89 to its binding post 86 thence via lead wire I to block 29 through closed contact members 3|, 45, switch arm 39 and its lead wire I", relay coil 96, lead wire 6, binding post III) and lead wire I35 back to the transformer secondary. Operation of the fan I26 will continue until the bonnet has been cooled sufliciently to cause counterclockwise rotation of shaft I by thermostatic coil 9 so that switch arm 86will be moved away, from supporting block I3 to disengagecontact member 93 from its contact member I6. .Disengagement of contact member 93 will be efiected with a snap action due to the attractive force of magnet" for theresilient switch blade 9| thereby-.preventing arcing between the contact members. The minimum bonnet temperature at which operation of the fan I26 is to be started may be regulated by adjusting. the position of supporting plate I9 about the shaft I. As

shown, the fan is set to be operated at a minimum temperature range which may be increased to require a higher bonnet temperature to start operation of the fan by clockwise rotation of plate I9, facing Fig. 2. The differential operation, that is, the difference between the temperature at which contact will be made between contact members 45 and 3| and the temperature at which contact will be broken therebetween may be regulated by adjusting the air gap between magnet 33 and switch blade 44 when the contact members are in engagement. This differential adjustment may be made either by adjusting the extent to which the contact member 3| projects from block 28 or by adjusting the magnet 33. It will be apparent that the closer the magnet end is .to the blade 44 when contact ismade, the lower the temperaturewill have to drop in the furnace bonnet relative to the temperature at which contact is madein order to break'the fan circuit. The maximum predetermined bonnet temperature at which the damper actuating means I24 will be deenergized to close the draft and open-the check dampers may be adiusted by rotation of supporting plate 55 which is shown set for the highest temperature adjustment.- counterclockwise rotation of supporting plate 55 about shaft I will result in breaking of contact between contact members 92 and 61 at a lower bonnet temperature. The differential operation may be adjusted as above described inconnection with switch arm 39 and contact will be broken at a given high tempera,- ture and will be made at a predetermined relatively lower temperature depending on the differential adjustment. The adjustment of supporting plate 55 will also adjust the position of contact member I6 to regulate the bonnet temperature at which the fan I26 will be started in the event the bonnet temperature goes too high, but the difference between the temperature at which the dampers will be closed by breaking of contact between contact members 92 and 61 and the temperature at which operation of the fan will be started will remain constant. If it is desired to change the temperature at which the fan will be started while maintaining constant the temperature at which the draft damper will be 'closed and the check damper opened, then the supporting plate 56 may be adjusted relative to supporting plate 55 by loosening the clamping screw 64. The differential between the temperature at which contact member 93 will engage contact member 16 to start operation of the fan and the relatively lower temperature at which engagement between contact members 16 and 93 will be broken to stop the fan may be adjusted by and fixed to said structure, a switch arm posi- :and said crank member tioned between said structure and. said crank member and journaled onsaid sleeve for movement thereabout bye-said crank member, a contact member engageabie by said arm, and a spring urging. said arm and said crank member into engagement.

2. A device of the character described, compris- 7 ing a supporting structure, a rotatable operating shaft journaled in said structure, means to rotate said shaft, a crankmember fixed on one end of said shaft, a bearing sleeve surrounding said. shaft and fixed to said structure, a switch arm positioned between said structure and said, crank member and Journaled on said sleeve, a contact member cooperable with said arm, and a coil spring surrounding said bearing sleeve, said spring having one end anchored to said arm and its other end anchoredv to said crank member and normally urging said crank member and said arm into engagement.

3. A device of the character described, comprising a supporting structure. a rotatable operating shaft journaled in said structure, means to rotate said shaft, a crank member fixed on one end of said shaft, a bearing sleeve surrounding said shaft and fixed to said structure, aswitch arm positioned between said structurev and said crank member and Journaled on said sleeve, an adjustable supporting member journaled on said sleeve,

a contact member cooperable with said armand carried by said supporting member, holding 'means cooperable with said structure and said supporting member to fix said supportingmember in adjusted position, and a spring urging said arm into engagement.-

4. A device of the character described, comprising a supporting structure, a rotatable operating shaft Journaled in saidstructure, means to rotate said shaft, a crank member fixed on said shaft, spaced abutment members of insulating material surrounding said shaft, a tubular insulating member surrounding said shaft and spacing said abutment members, a switch arm rotatable about said shaft and apertured to'receive said tubular member, said arm and said crank member being engageable whereby said arm is movable by said crank member, and a spring surrounding said tubular member and urging said arm into engagement with said crank member.

5. A device of the character described, comprising a supporting structure, a rotatable operating shaft journaied in said structure, means to rotate said shaft, a crank member fixed on said shaft, spaced abutment members of insulating material surrounding said shaft, a tubular insulating member surrounding said shaft and spacing said abutment members, a switch arm rotatable about said shaft and operable by said crank member, said switch arm being apertured to receive said tubular member, a tubular spacer member surrounding said tubular insulating member and spacing said switch arm from one of said abutment members, and a helical coil spring surrounding said tubular spaced member, said spring having one end anchored to said am and its other end anchored to said crank member and urging said arm and said crank member into engagement.

6. A device of the character described, comprising a supporting structure, a rotatable operating shaft journaled in said structure, means to rotate said shaft, a switch arm journaled about said shaft, a'second switch arm journaled about said shaft, .acrank member fixedtosaid shaft and cooperable with said'arms,,and a lostmotion connection between said crank member and one of said arms whereby said crank member is movable to actuate the other of said arms when said one arm has reached its limit of movement.

7. Adevice of the character described, com prising a supportlngstructure, a rotatable operating shaft journaled in said structure, means to rotate said shaft, aswitch arm Journaled about said shaft, ,an adjustable supporting member iournaled .about said shaft; a contact member carried by said supporting-member and cooperable -withsaid arm, a supporting member adjustably fixed to' said first-named supporting member, a contactmember carried by said second-named supporting member .and cooperable with said arm, and a crank memberon said shaft and operable to actuate said arm.

8. A device of the character described, comprising a supporting structure, a rotatable operating shaft-journaled in said structure, means to rotate said shaft, 8. switch arm journaled about said .shaft, and adjustable supporting member iournaled about said shaft, a contact member carried by said supporting member and cooperable with said arm, a second supporting member adjustab1y Journaled about said shaft asecond switch arm giournale'dabout said shaft, a contact member carried .by said second-named supporting member and cooperable with said'second-named switch arm, acrank member onsaid shaft and cooperablewith said arms, :and a lost-motion connection between saidcrank member and one of said arms'wherebysaid crank member is movable to actuate the other of said arms when said one arm engages its contact member.\

9. A device of the character described, comprising a casing having a .curved side wall, a rotatable operating shaftextending into said casing concentrically with said wall, a supporting member journaled about said shaft and tenninating adjacent said curved wall, said wall having a slot, clamping means extending radially of said shaft andv movable in'said slot and cooperable with said walland said supporting member to hold said supporting member in adjusted position, a contact member carried by said supporting member, and a switch arm extending radially from said shaft and cooperable with said contact member, said arm being operatively connected to said shaft.

10. A device of the character described, comprising a casing having a curved side wall, a

rotatable operating shaft extending into said casing concentrically with said wall, a supporting memberjournaled about said shaft and terminating adjacent saidwall, said wall having a slot, clamping means extending radially of said shaft and movable in said slot and cooperable with said wall and said supporting member to hold said supporting member in adjusted position, a contact member carried by said supporting member,-

structure and apertured to receive said shaft, a Contact member cooperable with said arm, and a coil spring surrounding said shaft and having one end anchored to said crank member and its other end anchored to said arm whereby to urge said on said shaft, a switch arm positioned between said structure and said crank member and journaled about said shaft, an adjustable supporting member journaled about said shaft, 9. contact member cooperable with said arm and carried by said supporting member, holding means cooperable with said structure and said supporting member to fix said supporting member in ad justed position, and a spring urging said arm and said crank member into engagement with each other.

. 13. A device of the character described, comprising a casing having'a curved side wall, a rotatable operating shaft in said casing and concentric with said wall, -a supporting member journaled about said shaft and terminating adjacent said wall, clamping means cooperable with and engaging said wall and said supporting member, said clamping means extending radially of said shaft and being operable to radially tension said supporting member to hold said supporting member in adjusted position; a contact member carried by said supporting member, and a switch arm extending radially from saidshaft and cooperable with said contact member, said arm being operatively connected to said shaft.

14. A device of the character described, comprising a supporting structure, a rotatable operating shaft carried by said structure, means to rotate said shaft, a switch arm journaled about said shaft, an adjustable supporting member journaled about said shaft, a contact member carried by said supporting member and cooperable with said arm, a second adjustable supporting member journaled about said shaft, means openable to hold said supporting members together for unitary adjustment, a contact member carried by said second-named supporting member and cooperable with said arm, and a crank member on said shaft and operable to actuate said arm.

15. A device of the character described, comprising a supporting structure, a rotatable shaft carried by said structure, means to rotate said shaft, a switch arm operable by said shaft, said arm comprising a member journaled about said shaft, said member having a transverse extension substantially parallel to said shaft, a backing plate extending from said extension in the plane of said shaft, a flexible switch blade extendin from said extension and along said plate, said blade and plate being relatively movable and said plate acting to reenforce said blade, and means fixing said blade and said plate to said extension.

16. A device of the character described comprising a supporting means, a shaft supported by said supporting means, means to rotate said shaft, a crank on said shaft, a sleeve member surrounding said shaft and carried by said supporting means, switch means including a movable contact member disposed between said supmeans porting means and said crank and carried by said sleeve member, a contact member cooperable with said movable member to controlan electric circuit, and lost-motion means urging said crank and said movable member into engagement.

17. A device of the character described comprising a supporting structure, an operating shaft rotatably carried by said structure, a member shaft and having a portion extendingradially of said shaft, a flexible switch blade secured to said member and extending along said radial portion, said blade and said portion being relatively movable and said portion acting to reenforce' said blade upon movement of said member in one direction, and lost-motion means operativelyconnecting said shaft and said member.

' 18. A device of the character'described comprising a supporting structure, an operating shaft rotatably carried by said structure, a member journaled for rotationaround said shaft and having a supporting face' substantially parallel to the longitudinal axis of said shaft, an elongated backing member secured to said journaled member and extending radially of said shaft, a flexible switch blade secured to said journaled member and extending radially of said shaft and along said backing member, said blade and saidba'cking member' bein'g rigidly fixed to said supportingface and being'movable relative to each other such that said backing member acts'to reenforce said blade upon movement of-said joumaled to secure said supporting members together in adjusted position, a contact member carried by said second supporting member and engageable by said arm, said arm extending between said contact members, and means operatively connecting said shaft and said switch arm. I a

20. A device of the character described comprising a supporting structure, an operating shaft rotatably supported by said structure, a switch arm journaled for rotation around said shaft, an adjustable supporting member extending radially from said shaft and movable concentric of said shaft, a contact member carried by said supporting member and engageable by said arm, a second supporting member adjustable relative to said first-named supporting member, means'to secure said supporting members together in adjusted position, a contact member carried by said second supporting member and engageable by said arm, said arm extending between said contact members, a crank member on and movable by said shaft, and resilient lost-motion means operatively connecting said crank member and said arm so that said arm is moved positively into engagement with one of said contact members 'and is movable by said lost-motion means into engagement with the other of said contact members.

EARNEST J. DILLMAN.

'journaied for rotation around and relative to said 

